1. Field of the Invention
The invention relates to a working process and to a device for carrying out a working process for regrinding rolls installed in hot-strip roll stands by means of pot-shaped grinding tools which are driven in rotation and are movable in an oscillating manner parallel to the roll axis. The grinding tool is fastened to the end of a grinding shaft which is driven in rotation so as to be axially displaceable transversely to the roll, guided coaxially in a grinding sleeve and connected at its opposite end with a displacing drive supported directly at the grinding sleeve.
2. Description of the Prior Art
A device of the generic type is provided for regrinding rolls which are installed in hot-strip roll stands, especially the work rolls in four-high roll stands. The contour of the roll can be reground while in the installed state in the roll stand by means of rotating pot-shaped grinding tools which are distributed along the length of the barrel or body of the roll to be ground and which are movable in an oscillating manner parallel to the roll axis together with the tool carrier receiving them and are independently adjustable transversely to the roll axis in a pressure-regulated manner. Every grinding tool is separately driven in rotation in such a way that it can be regulated with respect to speed.
In order to adjust the grinding tools toward the roll, the prior known solution suggests displacing the tailstock sleeve with the tools in the longitudinal direction by means of piston-cylinder units and thus controlling the path of the tool. The piston-cylinder units are regulated with respect to pressure and path, so that every grinding position and every grinding pressure can be controlled. The rotary drives for the grinding tools, preferably electric motors, are arranged at the end of the tailstock sleeve opposite to the grinding tool.
In the prior art, there is no mention of a method of applying the contact pressing force. The magnitude of the contact pressing force determines the grinding rate or removal rate of the grinding process. In particular, when grinding a roll with a plurality of grinding disks the contact pressing force of every disk must be identical so that no differences in diameter occur at the roll at the transition points between the paths of the individual grinding heads. Differences in diameter at the roll signify a jump in the surface which results in non-planar strips and accordingly leads to waste. Thus, the method of applying and transmitting the contact pressing force is very important for high-quality grinding.